Zinc deficiency and cellular immunity

Following a recommendation from the United Nations Committee on Nutrition, we evaluated the impact of daily oral supplementation of 10 mg of zinc sulfate on cellular immunity, respiratory infection incidence, and physical growth in malnourished children. A randomized, double-blind experimental study compared the effects of zinc administration versus placebo in a group of 50 malnourished children aged 12 to 59 months (mean age 37 months). The study lasted 120 days, divided into two periods: supplementation (days 0-60) and post-supplementation (days 61-120). On days 0, 60, and 120, the following variables were recorded: weight, height, zinc dosage, and skin response to the MULTITEST CMI. These variables were analyzed under similar socioeconomic and environmental conditions. Thirty-three well-nourished children were included as a control group. Each child was clinically observed for signs and symptoms of respiratory illness. Both instruments and techniques complied with international recommendations and were approved by the INEN (National Institute of Neoplastic Diseases). We accepted a p-value <0.05 as the significance threshold for each variable studied, subjected to the Student's t-test. The incidence (percentage) of respiratory signs and symptoms was examined using the Ch12 test. The eutrophic group responded better to the multitest (p <0.05). The incidence of children with low serum zinc levels was not significant (we considered serum zinc to be low at a value ≤ 75 µg/dL, which corresponded to -1 SD from the mean of the eutrophic group)...